This study presents the analysis and reduction of vertical crosstalk in mixed-signal 3-D integrated circuits (3-D ICs) with multilayer graphene nanoribbon (MLGNR) and multiwall carbon nanotube (MWCNT) interconnects. The 14-nm technology node is considered for both digital and analog tiers. The assessments are conducted regarding the scattering parameters (S-parameters) for the equivalent circuit model of the transmission lines using the Advanced Design System (ADS) tool. Our studies demonstrate that the MLGNR transmission lines lead to lower mismatch, insertion loss, and vertical crosstalk than their MWCNT counterparts. The results show that using MLGNR improves the area overhead by more than 67% for analog and digital wires. Moreover, our model shows that the vertical noise between the analog and digital tiers is reduced by 1 and 1.62 dB when the intermediate substrate thickness increases from 20 to 30 and $40~\mu \text{m}$ . The results demonstrate that the perpendicular routing of the MLGNR interconnects reduces the vertical noise by 6.1 dB. Moreover, a 9.21-dB reduction in the vertical coupling is achieved using vertical MLGNRs in the analog IC. Our results also show that using graphene as a shield between the analog and digital chips significantly suppresses the vertical noise between the tiers, and it becomes more effective by increasing the number of graphene layers. According to our results, using one-, two-, and three-layer graphene-shield layers reduces the vertical crosstalk by 10.1, 14.9, and 19.2 dB, respectively. Moreover, the HSPICE simulations demonstrate that the MLGNR interconnects have a lower delay, power, and energy consumption than their MWCNT counterparts in the 3-D mixed-signal architecture.

中文翻译：

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具有石墨烯纳米带和碳纳米管互连的3-D混合信号集成电路中的垂直噪声降低

这项研究提出了分析和减少具有多层石墨烯纳米带（MLGNR）和多壁碳纳米管（MWCNT）互连的混合信号3-D集成电路（3-D IC）中的垂直串扰的方法。数字和模拟层均考虑使用14纳米技术节点。使用高级设计系统（ADS）工具对传输线等效电路模型的散射参数（S参数）进行评估。我们的研究表明，MLGNR传输线比MWCNT传输线具有更低的失配，插入损耗和垂直串扰。结果表明，对于模拟和数字线，使用MLGNR可以将面积开销提高67％以上。此外，我们的模型表明，模拟层和数字层之间的垂直噪声降低了1和1。 $ 40〜\ mu \ text {m} $ 。结果表明，MLGNR互连的垂直布线可将垂直噪声降低6.1 dB。此外，在模拟IC中使用垂直MLGNR可以将垂直耦合降低9.21 dB。我们的结果还表明，使用石墨烯作为模拟芯片和数字芯片之间的屏蔽，可以显着抑制各层之间的垂直噪声，并且通过增加石墨烯层的数量，它可以变得更加有效。根据我们的结果，使用一层，两层和三层石墨烯屏蔽层可以分别将垂直串扰降低10.1、14.9和19.2 dB。此外，HSPICE仿真表明，与3D混合信号架构中的MWCNT同类产品相比，MLGNR互连具有更低的延迟，功耗和能耗。